Flash Flood in Morris County, Texas

Roadway flooded at the intersection of Spur 284 and FM 114 in Omaha.

A prolonged period of very heavy rainfall along with severe thunderstorms occurred on October 4th-5th across parts of Northeast Texas. Showers and thunderstorms with 1-3 inch per hour rainfall rates trained in the vicinity of a warm front, which was oriented across the Ark-La-Tex and in adjacent portions of Southeast Oklahoma and Northeast Louisiana. Deep convergence of moisture along the boundary resulted as the core of the low-level jet and associated moisture transport was directed due north from the Upper Texas coast. Other factors contributing to the heavy rainfall and severe storms included a sharp instability gradient with mean-layer CAPE values from 500-1500 J/kg, maximized precipitable water values from 2.0-2.2 inches and effective bulk shear of 25-30 knots. As a result, this area of Northeast Texas quickly became more favorable for increasing convective organization as multi-cell thunderstorms continued to train over the same areas from late morning throughout much of the afternoon and evening. Over time, flash flooding developed in areas impacted by 4-8 inch rainfall totals, most notably in and around the Texarkana metro area. Severe impacts from damaging wind gusts occurred farther south closer to the Interstate 20 corridor.